A communication system can be seen as a facility that enables communication sessions between two or more entities such as one or more communication devices and/or other nodes associated with the communication system. A communication system typically operates in accordance with a given standard or specification setting out what the various entities associated with the communication system are permitted to do and how that should be achieved. A standard or specification may define a specific set of rules, such as communication protocols and/or parameters, on which connections between the entities can be based.
Wireless communication systems include various cellular or otherwise mobile communication systems using radio frequencies for sending voice or data between, stations, for example between a communication device and a transceiver network element. National or international authorities or organizations may allocate a radio frequency band, so-called licensed radio frequencies, to mobile communication networks. Examples of mobile communication systems operating on a licensed spectrum may comprise a public land mobile network (PLMN), such as global system for mobile communication (GSM), general packet radio service (GPRS), and third generation (3G) networks, such as universal mobile telecommunications system (UMTS). The 3G network may use wideband code division multiple access (W-CDMA) technology or other air interfaces, such as the enhanced data rates for global evolution (EDGE), multi-carrier code division multiple access (CDMA2000).
A mobile communication network may logically be divided into a radio access network (RAN) and a core network (CN). A communication device may access the communication network via an access entity, such as a transceiver network element, of the RAN. Examples of radio access networks operating on a licensed spectrum may comprise GSM/EDGE radio access network (GERAN) and UMTS terrestrial radio access network (UTRAN).
A single communication system may interface with one or more communication systems, such as with other wireless systems, such as a wireless Internet Protocol (IP) network, wireless local area network (WLAN) and/or fixed line communication systems.
Wireless communication systems may also use unlicensed radio frequencies. Unlicensed Mobile Access (UMA) technology provides access to mobile services over unlicensed spectrum technologies. Examples of unlicensed spectrum technologies may comprise Bluetooth and IEEE 802.11, both operating in an unlicensed 2.4 GHz industrial, scientific and medical (ISM) frequency band.
UMA is an extension of GSM/GPRS/UMTS mobile services into customer premises achieved by tunneling certain GSM/GPRS/UMTS protocols between the customer premises and the core network over a broadband IP network. In UMA, unlicensed spectrum technologies may be used to carry another access protocol, such as GSM, GPRS or UMTS, to reach the GSM/GPRS/UMTS core network when the core network is not directly reachable. From a perspective of an end-user, GSM/GPRS/UMTS services are used. UMA is a complement to a traditional GSM/GPRS/UMTS radio coverage, used to enhance customer premises coverage, increase network capacity and potentially lower costs.
A communication device may establish a packet data connection to a UMA network controller (UNC). Each UNC may control a plurality of UMA cells. The UNC may be connected to one or more controlling or switching elements of the mobile communication systems, such as to one or more serving GPRS support nodes (SGSN). In the GSM/GPRS/UMTS, the SGSN is a network element, which typically keeps track of a location of an individual communication device and performs security functions and access control.
It might be desired to provide a way that the UNC, or another controller network element of unlicensed radio spectrum access network, was able to decide with which controlling or switching element of the core network, in particular with which SGSN, to communicate. This might provide advantages in various situations. A particular example may be a situation where a single SGSN is serving both UMA and GPRS/UMTS cells.